Red berry mite

Red berry mite is a microscopic invertebrate that can cause of uneven ripening of blackberries.

Red berry mite damage on blackberry fruits

Quick facts

Common name: Red berry mite, blackberry mite, ‘red-berry’ disease
Scientific name: Acalitus essigi
Plants affected: Blackberries
Main symptoms: Uneven ripening of fruit
Most active: April-September

What is red berry mite?

Red berry mite is a microscopic (<0.2mm) whitish mite that sucks sap from flowers and fruit of blackberries, causing uneven ripening. It does not affect other cane fruits.


Red berry mites overwinter under bud scales and become active on the foliage during the spring. When in bloom the mites move onto the flowers and developing fruits.

The first fruits to develop usually ripen fully but later fruits show increasingly patchy ripening, with some parts of the berries remaining hard and red or green. The patchy ripening is sometimes referred to as ‘red-berry’ disease.


There are no suitable pesticides available to home gardeners for control of the mite and so the damage has to be tolerated. Heavily affected canes can be cut to ground level as soon as the problem is noticed and binned (including council compost) or burnt. Consider replacing canes with persistent problems of red berry mite.

Partly ripened berries can be used for cooking, making jam or wine.

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